Random splicing of conductor pairs within groups in cables, especially those having pulp-insulated conductors, is generally desirable to avoid electrical degradation resulting from systematic addition of capacitance unbalances in the transmission lines. However, where a pulp cable has been installed and then accidentally cut, restoration of the cable requires matching up of the cut conductor pairs for splicing. Such a chore is unduly burdensome as pulp cables are typically grouped into large groups of 100 or 50 unidentified pairs and requires that repairmen identify each conductor pair by verification and identification testing.
Complete color coding of such cables is not generally desirable since pair identification is not often needed and to maintain pair identity by always splicing according to a color code would substantially increase splicing cost. Also, the manufacturing cost can increase substantially, especially when setting up an inventory of conductors of many colors. Also, the more colors there are, the more mistakes a workman can make during splicing, as the identifying colors approach each other in shade. Furthermore, unlike polyethylene insulation, pulp insulation does not offer a wide variety of distinguishable colors.
Hence, it is desirable to develop a scheme which permits unique identification of the conductor pairs by visual examination when a cable needs to be restored at a minimum of added manufacture cost and at a reduced reliance on color.
Accordingly, it is one object of this invention to develop an improved cable design which facilitates identification of all conductor pairs in the cable by visual examination.
It is another object of this invention that the cable design be of minimum added cost to manufacture.
A further object of this invention is that the improved cable design be more compatible with modular connectors that are increasingly implemented in the field.